machine-id-commit: merge machine-id-commit functionality into machine-id-setup

And remove machine-id-commit as separate binary.

There's really no point in keeping this separate, as the sources are
pretty much identical, and have pretty identical interfaces. Let's unify
this in one binary.

Given that machine-id-commit was a private binary of systemd (shipped in
/usr/lib/) removing the tool is not an API break.

While we are at it, improve the documentation of the command substantially.

src/machine-id-commit/Makefile

@@ -1 +0,0 @@
-../Makefile

src/machine-id-commit/machine-id-commit.c

@@ -1,105 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
-  This file is part of systemd.
-
-  Copyright 2014 Didier Roche
-
-  systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU Lesser General Public License as published by
-  the Free Software Foundation; either version 2.1 of the License, or
-  (at your option) any later version.
-
-  systemd is distributed in the hope that it will be useful, but
-  WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public License
-  along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <errno.h>
-#include <getopt.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#include "log.h"
-#include "machine-id-setup.h"
-#include "util.h"
-
-static const char *arg_root = NULL;
-
-static void help(void) {
-        printf("%s [OPTIONS...]\n\n"
-               "Commit a transient /etc/machine-id on disk if writable.\n\n"
-               "  -h --help             Show this help\n"
-               "     --version          Show package version\n"
-               "     --root=ROOT        Filesystem root\n",
-               program_invocation_short_name);
-}
-
-static int parse_argv(int argc, char *argv[]) {
-
-        enum {
-                ARG_VERSION = 0x100,
-                ARG_ROOT,
-        };
-
-        static const struct option options[] = {
-                { "help",      no_argument,       NULL, 'h'           },
-                { "version",   no_argument,       NULL, ARG_VERSION   },
-                { "root",      required_argument, NULL, ARG_ROOT      },
-                {}
-        };
-
-        int c;
-
-        assert(argc >= 0);
-        assert(argv);
-
-        while ((c = getopt_long(argc, argv, "hqcv", options, NULL)) >= 0)
-                switch (c) {
-
-                case 'h':
-                        help();
-                        return 0;
-
-                case ARG_VERSION:
-                        return version();
-
-                case ARG_ROOT:
-                        arg_root = optarg;
-                        break;
-
-                case '?':
-                        return -EINVAL;
-
-                default:
-                        assert_not_reached("Unhandled option");
-                }
-
-        if (optind < argc) {
-                log_error("Extraneous arguments");
-                return -EINVAL;
-        }
-
-        return 1;
-}
-
-int main(int argc, char *argv[]) {
-        int r;
-
-        log_set_target(LOG_TARGET_AUTO);
-        log_parse_environment();
-        log_open();
-
-        r = parse_argv(argc, argv);
-        if (r <= 0)
-                goto finish;
-
-        r = machine_id_commit(arg_root);
-
-finish:
-        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
-}

src/machine-id-setup/machine-id-setup-main.c

@@ -28,15 +28,17 @@
 #include "machine-id-setup.h"
 #include "util.h"
 
-static const char *arg_root = "";
+static const char *arg_root = NULL;
+static bool arg_commit = false;
 
 static void help(void) {
         printf("%s [OPTIONS...]\n\n"
                "Initialize /etc/machine-id from a random source.\n\n"
                "  -h --help             Show this help\n"
                "     --version          Show package version\n"
-               "     --root=ROOT        Filesystem root\n",
-               program_invocation_short_name);
+               "     --root=ROOT        Filesystem root\n"
+               "     --commit           Commit transient ID\n"
+               , program_invocation_short_name);
 }
 
 static int parse_argv(int argc, char *argv[]) {
@@ -44,12 +46,14 @@ static int parse_argv(int argc, char *argv[]) {
         enum {
                 ARG_VERSION = 0x100,
                 ARG_ROOT,
+                ARG_COMMIT,
         };
 
         static const struct option options[] = {
                 { "help",      no_argument,       NULL, 'h'           },
                 { "version",   no_argument,       NULL, ARG_VERSION   },
                 { "root",      required_argument, NULL, ARG_ROOT      },
+                { "commit",    no_argument,       NULL, ARG_COMMIT    },
                 {}
         };
 
@@ -73,6 +77,10 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_root = optarg;
                         break;
 
+                case ARG_COMMIT:
+                        arg_commit = true;
+                        break;
+
                 case '?':
                         return -EINVAL;
 
@@ -98,5 +106,11 @@ int main(int argc, char *argv[]) {
         if (r <= 0)
                 return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 
-        return machine_id_setup(arg_root) < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+        if (arg_commit)
+                r = machine_id_commit(arg_root);
+        else
+                r = machine_id_setup(arg_root);
+
+
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 }